Goal cost column on reports and dashboard

I set up a goal and can see my revenue, but I don't see the cost figure anywhere. What am I doing wrong?

I would like to see the cost column on my goals dashboard. Anyone know how to do this?

The cost of what?

Sorry, I was not clear. The goals feature allows you to specify a revenue number and a cost for each goal. I can see the revenue totals, just not the cost totals.